Allowance For Loan Losses And Credit Quality Of Financing Receivables - Loans Which The Accrual Of Interest Has Been Discontinued (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans for which accrual of interest has been discounted	$ 5,448	$ 5,833
Commercial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans for which accrual of interest has been discounted	19	33
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans for which accrual of interest has been discounted	3,843	4,048
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans for which accrual of interest has been discounted	$ 1,586	$ 1,752